Amber
- Amber is mined in three areas of the Dominican Republic. The first group of mines are located in the mountains north of the city of Santiago. The second group of mines in the area surrounding the town of El Valle, is northeast of the capital of Santo Domingo. Dominican amber was formed from an extincted species of the genus Hymenaea. Science has determined that this Dominican amber tree is more closely related to a living species found in Africa, (H. verrucosa) than any found in the Americas. A variety of organisms have been discovered "trapped" in this amber. Inferences of the composition of the amber forest can be made based on these inclusions. An organism occupies a specific niche in the environment. If an amber insect has living relatives that exclusively feeds on a certain genus of tree, the assumption is that the extinct species also fed upon this genus.

The amber on the island generally occurs in layers of lignite or carbonaceous clay interspersed with beds of sandstone. The sequences are different for the various amber locations but generally these geological elements are always present. The amber usually occurs as small fragments or small nodules usually no bigger than few centimetres across, although bigger pieces are found The biggest ever discovered weighing 18 pounds, but this size is the exception and not the rule.

The age of these deposits varies. The youngest originate from Cotui which has been estimated to be between 15-17 Million years old. The oldest amber is located in the Cordillera Septentrional and has been established as 30-40 million years old. A total time span of some 25 million years for all of the amber deposits. The majority therefore comes from the Oligocene and Miocene. All of the deposits so far discovered on the island are thought to be secondary. That is to say the amber has been moved and re-deposited from its location where it was first laid down.